In the first terror strike in the city since 2007, the two near-simultaneous explosions occurred in Dilsukhnagar area, south of Musi River in the southern part of the Andhra Pradesh capital and about 15 km from the heart of the city, when the busy commercial area was crowded with people returning home.

According to some eyewitness accounts, three explosions were heard but most said they heard two loud explosions within a couple of minutes.

The first blast occurred around 7 p.m. near a tiffin centre opposite Venkatadri theatre and the second near Konark theatre. The bombs were planted on bicycles.

Ambulances and police vehicles rushed to the area. The injured were shifted to Yashoda Hospital at Malakpet and to the government-run Osmania Hospital. Gory pictures of the victims without limbs were seen. Others with bleeding injuries were shifted to ambulances.

Initially people believed it to be an explosion of a gas cylinder at the tiffin centre but the second explosion soon after triggered panic in the area. An eye witness told reporters that people ran in panic. Some people using the foot-over-bridge in the area were those among killed and injured.

So powerful were the explosions that the body parts of some of the victims were found several meters away from the scene. Ammonium nitrate is suspected to have been used for the blasts.

The area was cordoned off as senior police officials and sleuths from National Investigation Agency (NIA) and Intelligence Bureau rushed to the scene.

Chief Minister N. Kiran Kumar Reddy, Home Minister Sabita Indra Reddy, Director General of Police V. Dinesh Reddy and others visited the scene in the area, close to Hyderabad-Vijayawada highway.

The area faced its second terrorist strike in over 10 years. Two people were killed in an explosion near Saibaba Temple on Nov 21, 2002. The Lashkar-e-Toiba had been held responsible.

In Delhi, Union Home Minister Sushilkumar Shinde admitted the government had received intelligence warning of blasts taking place in the country but no specific target was mentioned.

"We were receiving information for the last two days that such a blast may take place... there was no input about which city would be targeted," Shinde told reporters adding that the information was passed onto all the states.

"We cannot speculate about the perpetrators at this point of time," he said further.

Union Home Secretary R.K. Singh put the number of dead at 12. "Twin blasts have occurred. The number of dead has increased from 10 to 12 and the injured are 57," he told reporters after holding a high-level security meet.

NIA and the National Security Guard (NSG) teams have been sent to Hyderabad, he said.

The Andhra chief minister put the toll at 11 dead and 80 injured, of which five to six were in serious condition.

"We condemn this barbaric act. The state government along with central government will see to it that the culprits are booked as early as possible," said Kiran Reddy at a a press conference, appealing to people to maintain peace.

He announced an ex-gratia of Rs.6 lakh to each the kin of those killed and Rs.50,000 to Rs.1 lakh to the injured depending on the severity of their injuries. He also declared that the state government would bear the cost of their treatment.

The chief minister said Prime Minister Manmohan Singh, United Progressive Alliance (UPA) chairperson Sonia Gandhi and Shinde spoke to him. "They assured all help from the centre and asked us to be alert about any such incidents happening again."

Strongly condemning the twin blasts, the prime minister described it as a "dastardly attack" and said the guilty should not "go unpunished".

"This is a dastardly attack, the guilty will not go unpunished," a tweet from the Prime Minister's Office (PMO) quoted Manmohan Singh as saying.